Background: This study investigated the clinical characteristics, cranial magnetic resonance imaging (MRI) features, MRI follow-up, and prognosis of children with acute lymphoblastic leukemia (ALL) who developed posterior reversible encephalopathy syndrome (PRES) during remission induction chemotherapy.
Methods: We analyzed the age, gender, PRES symptoms and signs, cranial MRI findings, therapeutic effect, and prognosis of children with ALL who developed PRES during chemotherapy from January 2010 to December 2013 at the Hematology Oncology Center of Beijing Children's Hospital. Changes in cranial MRI findings were analyzed, and intelligence (IQ) and cognitive function were evaluated using the Wechsler Scale and the Wisconsin Card Score Test after the children completed chemotherapy.
Results: There were 850 children with newly diagnosed ALL in this period; 13 (1.5%), 6 boys and 7 girls, developed PRES. All were diagnosed as B-cell ALL. The median age at PRES onset was 7 years (2-11 years). The median day of PRES onset was day 28 (day 17-34) of remission induction chemotherapy. Of the 13 children with PRES onset and seizures, 4 had visual disturbances and 2 had consciousness disturbances. Cranial MRI showed hyperintensity in the subcortical white matter on T2-weighted axial and fluid-attenuated inversion recovery (FLAIR) images. The lesion locations were as follows: occipital lobe, 12 (92.3%) patients; frontal lobe, 7 (53.8%) patients; temporal lobe, 5 (38.4%) patients; parietal lobe, 3 (23.1%) patients; and cerebellum, 1 (7.7%) patient. There were 8 (61.5%) patients with vasogenic edema and 5 (38.5%) with cytotoxic edema. After treatment, all children recovered within one month, when their PRES symptoms were relieved, they continued to receive chemotherapy. However, 1 child (1.07%) died of severe central nervous system infection one year after PRES treatment, and 3 (25%) had recurrent seizures and were diagnosed with epilepsy after three months of PRES treatment. Their cranial MRIs showed cytotoxic edema, which was acute stage on day 15, with aggravated lesions on cranial MRI. The cranial MRI lesions returned to normal at one month in 3 (23.1%) patients, at three months in 6 (46.1%) patients, at one year in 8 (61.5%) patients, and at two years in 12 (92.3%) patients. The 12 surviving children all returned to school, and their full-scale, verbal, and performance IQs were normal, with no significant differences in intelligence or cognitive function compared with children with ALL without PRES during the same period.
Conclusions: PRES can occur during remission induction chemotherapy treatment of children with ALL, but the incidence is low. Cranial MRI can be used for diagnosis and to characterize lesions. The children recover about a month after treatment, and cranial MRI lesions return to normal within two years. The time for complete resolution of MRI lesions differs, and children with cytotoxic edema have worse prognosis with sequelae, such as epilepsy, which requires close monitoring. PRES does not affect intelligence or cognitive development.